San Diego  Hundreds of teachers turned their classrooms over to substitutes Wednesday to contest pink slips — or simply protest the San Diego school district’s massive proposed personnel cuts — at hearings that give educators a last-ditch effort to save their jobs.

Many showed up in red union T-shirts and carried picket signs. Some brought stacks of papers to grade while they waited through the tedious proceedings. A few even arrived with babies, whose pediatric health care could be cut along with their parents’ jobs.

The San Diego Unified School District issued tentative layoff notices to 1,666 teachers — including 20 percent of the elementary teaching force — last month to cope with the state’s fiscal crisis and help offset a projected $122 million deficit in next year’s $1.1 billion budget.

The district says union concessions — in the way of teachers forgoing raises, extending furloughs and accepting changes to health care — would save jobs. The union, on the other hand, has criticized the district for exaggerating the budget crisis and failing to consider savings realized through retirements and resignations.

Nearly 1,100 teachers requested hearings to fight their layoff notices this week. Pink slips are issued based on a teacher’s seniority, subject credentials and training certificates. Some worried the district wouldn’t cancel layoffs as it has done in previous years.

“When I got my pink slip, I didn’t really worry since I’ve been with the district so long — 12 years,” said Kimberly Bazon, a Sherman Elementary School teacher who brought her 2-month-old son to the proceedings. “But now that we’ve made it to hearings and not one pink slip has been rescinded, I’m starting to get a little worried.”

Teachers may take up to three days off to attend the hearings, which are held in the Kearny High School auditorium through Friday. With an administrative law judge presiding and lawyers from the district and San Diego Education Association present, teachers have a chance to make a case to get their pink slips rescinded.

Larry Schoenke, the district’s chief counsel, told the crowd pink slips were issued to balance the budget and administered under the law — without judgment on individual teachers.

“This is all driven by the education code,” he said. “It’s something that no one in the district wants to do.”

San Diego Unified received 550 requests for substitute teachers Wednesday at a crucial time, because some schools are set to begin administering state standardized tests this week. Not every educator at the hearings will require a substitute, because year-round schools are not in session. The district isn’t required to cover for counselors and nurses.

Some teachers attended the hearings to protest the state’s system for financing schools, one that calls for districts to adopt budgets months before they know how much money the state will give them. Others wanted to show the district how tough it would be to operate schools without 1,600-plus employees next year.

“It will be impossible for schools to open in September,” said Stefanie Gaines, who teaches art and French at Mira Mesa High School. “I have 38 students in a class today; imagine what it’s going to look like with 1,600 fewer educators.”

Among those who turned out were some acclaimed educators whose pink slips underscore the consequences of seniority-based hiring and firing practices.

Six former teachers of the year at Lincoln High School, a long-struggling campus that reopened after a multimillion-dollar renovation five years ago, showed up, even though they don’t believe they have a case to make for a rescission. At Lincoln, 32 of 67 teachers are set to be laid off and replaced by more seasoned educators who may not even want to work at the campus.

“Building relationships and earning trust with students is key — and it takes time — especially at schools like Lincoln,” said English teacher Christopher Dier.

Schools in poor neighborhoods were hit hard by layoffs, since they historically employee the least-experienced teachers. Veteran educators often use their seniority to get jobs in suburban campuses where teaching hurdles such as crime, language barriers and poverty aren’t as big.

The hearing judge has until May 7 to make recommendations to the school board to rescind any pink slips. Last year, of the 325 teachers who requested hearing, 20 had their pink slips rescinded.